1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
|
/*=========================================================================
*
* Copyright NumFOCUS
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0.txt
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*=========================================================================*/
// Software Guide : BeginLatex
//
// The \doxygen{RelabelComponentImageFilter} is commonly used for
// reorganizing the labels in an image that has been produced as the result
// of a segmentation method. For example, region growing, or a K-means
// statistical classification.
//
// \index{itk::RelabelComponentImageFilter}
//
// Software Guide : EndLatex
#include "itkImageFileReader.h"
#include "itkImageFileWriter.h"
// Software Guide : BeginLatex
//
// The header file corresponding to this filter should be included first.
//
// \index{itk::RelabelComponentImageFilter!header}
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
#include "itkRelabelComponentImageFilter.h"
// Software Guide : EndCodeSnippet
int
main(int argc, char * argv[])
{
if (argc < 3)
{
std::cerr << "Usage: " << std::endl;
std::cerr << argv[0] << " inputImageFile outputImageFile" << std::endl;
return EXIT_FAILURE;
}
// Software Guide : BeginLatex
//
// Then the pixel types for input and output image must be defined and,
// with them, the image types can be instantiated.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
using InputPixelType = unsigned char;
using OutputPixelType = unsigned char;
using InputImageType = itk::Image<InputPixelType, 2>;
using OutputImageType = itk::Image<OutputPixelType, 2>;
// Software Guide : EndCodeSnippet
using ReaderType = itk::ImageFileReader<InputImageType>;
using WriterType = itk::ImageFileWriter<OutputImageType>;
auto reader = ReaderType::New();
auto writer = WriterType::New();
reader->SetFileName(argv[1]);
writer->SetFileName(argv[2]);
// Software Guide : BeginLatex
//
// Using the image types it is now possible to instantiate the filter type
// and create the filter object.
//
// \index{itk::RelabelComponentImageFilter!instantiation}
// \index{itk::RelabelComponentImageFilter!New()}
// \index{itk::RelabelComponentImageFilter!Pointer}
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
using FilterType =
itk::RelabelComponentImageFilter<InputImageType, OutputImageType>;
auto relabeler = FilterType::New();
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// The input to the filter can be taken from any other filter, for example
// a reader. The output can be passed down the pipeline to other filters,
// for example, a writer. An update call on any downstream filter will
// trigger the execution of the mean filter.
//
// \index{itk::RelabelComponentImageFilter!SetInput()}
// \index{itk::RelabelComponentImageFilter!GetOutput()}
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
relabeler->SetInput(reader->GetOutput());
writer->SetInput(relabeler->GetOutput());
writer->Update();
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// We can now query the size of each one of the connected components, both
// in pixel units and in physical units.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
using SizesInPixelsType = std::vector<itk::SizeValueType>;
const SizesInPixelsType & sizesInPixels =
relabeler->GetSizeOfObjectsInPixels();
auto sizeItr = sizesInPixels.begin();
auto sizeEnd = sizesInPixels.end();
std::cout << "Number of pixels per class " << std::endl;
unsigned int kclass = 0;
while (sizeItr != sizeEnd)
{
std::cout << "Class " << kclass << " = " << *sizeItr << std::endl;
++kclass;
++sizeItr;
}
// Software Guide : EndCodeSnippet
// Software Guide : BeginCodeSnippet
using SizesInPhysicalUnitsType = std::vector<float>;
const SizesInPhysicalUnitsType sizesInUnits =
relabeler->GetSizeOfObjectsInPhysicalUnits();
auto physicalSizeItr = sizesInUnits.begin();
auto physicalSizeEnd = sizesInUnits.end();
std::cout << "Area in Physical Units per class " << std::endl;
unsigned int jclass = 0;
while (physicalSizeItr != physicalSizeEnd)
{
std::cout << "Class " << jclass << " = " << *physicalSizeItr << std::endl;
++jclass;
++physicalSizeItr;
}
// Software Guide : EndCodeSnippet
return EXIT_SUCCESS;
}
|
